JP5441952B2 - Conductive polymer suspension and method for producing the same, conductive polymer material, and electrolytic capacitor and method for producing the same - Google Patents

Description

  Embodiments according to the present invention relate to a conductive polymer suspension solution and a manufacturing method thereof, a conductive polymer material obtained from the suspension solution, an electrolytic capacitor using the same, and a manufacturing method thereof.

  Conductive polymer materials are used for electrodes for capacitors, electrodes for dye-sensitized solar cells, electrodes for electroluminescence displays, and the like. As such a conductive polymer material, a polymer material obtained by increasing the molecular weight of pyrrole, thiophene, 3,4-ethylenedioxythiophene, aniline, etc. is known, and related techniques are disclosed in Patent Documents 1 to 3. Has been.

  Patent Document 1 relates to a solution (dispersion) of polythiophene, a production method thereof, and the use of a salt for antistatic treatment of a plastic molded body. Specifically, a polythiophene dispersion composed of structural units of 3,4-dialkoxythiophene in the presence of a polyanion (polyanion) is described. It is described that this polythiophene dispersion is produced by oxidative polymerization of 3,4-dialkoxythiophene at a temperature of 0 to 100 ° C. in the presence of a polyanion.

  Patent Document 2 discloses an aqueous dispersion of a complex of poly (3,4-dialkoxythiophene) and a polyanion, a method for producing the same, a coating composition containing the aqueous dispersion, and the composition applied. The present invention relates to a coated substrate having a transparent conductive film. Specifically, poly (3,4-dialkoxythiophene produced by polymerizing 3,4-dialkoxythiophene in an aqueous solvent using peroxodisulfuric acid as an oxidizing agent in the presence of a polyanion. ) And polyanions in aqueous dispersions are described.

  US Pat. No. 6,057,049 discloses a dispersion comprising polystyrene sulfonic acid and 3,4-polyethylenedioxythiophene, wherein at least 90% by weight of the particles have a particle size of less than 50 nm, and hole injection made from the dispersion. The invention relates to an electroluminescent device comprising a layer. By reducing the particle size in the dispersion comprising polystyrene sulfonic acid and 3,4-polyethylenedioxythiophene by at least 90% by weight less than 50 nm, without losing the desired hole injection effect, It is described that the resistance of 4-polyethylenedioxythiophene can be increased.

JP 07-090060 A JP 2004-059666 A JP 2002-305086 A

  However, in the method of oxidative chemical polymerization of 3,4-dialkoxythiophene in the presence of a polyanion acting as a dopant, it is difficult to control the doping rate, and an undoped polyanion, that is, a polyanion that does not contribute to conductivity is not obtained. It exists in surplus. Therefore, the methods described in Patent Documents 1 and 2 are hardly sufficient as a method for producing a polymer material having high conductivity.

In addition, the surface resistivity of antistatic materials is generally classified as 10 ⁵ to 10 ¹⁴ Ω / □, and if the conductivity is too high (less than 10 ⁵ Ω / □), it may cause severe electrostatic discharge. Therefore, it is considered that the antistatic material does not have conductivity enough to quickly dissipate static electricity of a charged object. Even when the conductivity is sufficient as an antistatic material, for example, when used as an electrode of a capacitor, it is difficult to sufficiently satisfy the requirement for low ESR from the viewpoint of conductivity. In addition, since conductive polymer materials containing excess poly anions have very poor water resistance, capacitors using such conductive polymer materials as electrolytes are reliable, especially in high humidity environments. There is a disadvantage that the characteristics below are inferior.

The method described in U.S. Patent No. 6,057,049 is based on 90 wt% polystyrene sulfonic acid and 3,4-polyethylenedioxythiophene in a dispersion to increase resistance to suit the hole injection layer of the electroluminescent device. The particle size is 50 nm or less, and the coating agent made from the dispersion has low conductivity (> 5000 Ωcm; less than 2 × 10 ⁻⁴ S / cm). Therefore, as in Patent Documents 1 and 2, for example, when used as an electrode of a capacitor, it is difficult to sufficiently satisfy the requirement for low ESR from the viewpoint of conductivity.

  An object of an embodiment according to the present invention is to solve the above-described problem, to provide a conductive polymer suspension solution for providing a high-conductivity polymer material and a method for producing the same, and It is an object of the present invention to provide an electrolytic capacitor excellent in characteristics at low ESR and reliability, particularly in a high humidity atmosphere, and a manufacturing method thereof.

An embodiment according to the present invention contains a conductive polymer, at least one polyanion, and at least one dispersant having a branched structure,
The conductive polymer includes a conductive polymer having a particle size of 100 nm or less,
The dispersant having the branched structure has an adsorption group for adsorbing to the conductive polymer in the main chain, and has one or more hydrophilic side chains and one or more hydrophobic side chains. Consisting of a structure
The main chain is selected from polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, acrylic resin and a copolymer having these structural units,
The adsorbing group is selected from a carboxyl group, a sulfo group, a phosphate group and an amino group,
The side chain has a hydrophilic side chain and a hydrophobic side chain, and the hydrophilic side chain is selected from polyether, polyvinyl alcohol and polyvinyl pyrrolidone, and the hydrophobic side chain is polyethylene. Selected from polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate and acrylic resin ,
The conductive polymer comprising 10 to 200 parts by weight of the polyanion and 1 to 120 parts by weight of the dispersant having the branched structure with respect to 100 parts by weight of the conductive polymer. Suspension solution.

Embodiments of the present invention, all of the conductive polymer is a conductive polymer suspension for equal to or less than the particle size of 100 nm.

Embodiments according to the present invention
A first step of obtaining a mixture containing a conductive polymer by chemically oxidatively polymerizing a monomer which gives a conductive polymer in a solvent containing an organic acid or a salt thereof as a dopant using an oxidizing agent;
A second step of recovering the conductive polymer from the mixture;
A third step of mixing an oxidizing agent with the conductive polymer in an aqueous solvent containing a polyanion;
After mixing the dispersing agent having a branched structure, a conductive polymer, it has a a fourth step of pulverizing such that the particle size include the following conductive polymer 100 nm,
The dispersant having the branched structure has an adsorption group for adsorbing to the conductive polymer in the main chain, and has one or more hydrophilic side chains and one or more hydrophobic side chains. Consisting of a structure
The main chain is selected from polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, acrylic resin and a copolymer having these structural units,
The adsorbing group is selected from a carboxyl group, a sulfo group, a phosphate group and an amino group,
The side chain has a hydrophilic side chain and a hydrophobic side chain, and the hydrophilic side chain is selected from polyether, polyvinyl alcohol and polyvinyl pyrrolidone, and the hydrophobic side chain is polyethylene. A method for producing a conductive polymer suspension solution characterized by being selected from polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, and acrylic resin .

  An embodiment according to the present invention is a conductive polymer suspension solution obtained by the above method.

  An embodiment according to the present invention is a conductive polymer material, wherein the conductive polymer suspension solution is dried to remove the solvent.

  An embodiment according to the present invention is an electrolytic capacitor having the above-described conductive polymer suspension solution or an electrolyte layer containing the above conductive polymer material.

Embodiments according to the present invention
Forming a dielectric layer on the surface of the anode conductor made of a valve metal;
And a step of coating or impregnating the conductive polymer suspension solution on the dielectric layer to form an electrolyte layer.

Embodiments according to the present invention
Forming a dielectric layer on the surface of the anode conductor made of a valve metal;
Forming a first conductive polymer compound layer on the dielectric layer by chemical oxidative polymerization or electrolytic polymerization of a monomer that gives the first conductive polymer compound;
Applying or impregnating the conductive polymer suspension solution on the first conductive polymer compound layer to form a second conductive polymer compound layer. This is a method of manufacturing a capacitor.

  According to the embodiment of the present invention, a conductive polymer suspension solution for providing an organic material having high conductivity, adhesion to a substrate and excellent water resistance can be obtained. Further, according to the embodiment of the present invention, an electrolytic capacitor having low ESR and reliability, particularly excellent characteristics in a high humidity atmosphere can be obtained.

It is typical sectional drawing which shows the structure of the solid electrolytic capacitor which concerns on this embodiment.

  Hereinafter, a conductive polymer suspension solution according to the present embodiment, a conductive polymer material obtained from the suspension solution, a method for producing a conductive polymer suspension solution, and an electrolytic capacitor using the conductive polymer material The manufacturing method thereof will be described in detail.

<Conductive polymer suspension and conductive organic material>
The conductive polymer suspension according to this embodiment contains a conductive polymer, at least one polyanion, and at least one dispersant having a branched structure.

  By setting it as the said structure, a conductive polymer suspension solution is excellent in the dispersion stability of the particle | grains to contain. Therefore, the undoped polyanion, that is, the polyanion that does not contribute to conductivity can be reduced with respect to the conductive polymer, and the conductive polymer material obtained from the conductive polymer suspension solution has a high conductivity. It is. In addition, since it does not contain excessive polyanions, the conductive polymer material obtained from the conductive polymer suspension solution has excellent water resistance, and the capacitor using the conductive polymer material as an electrolyte is reliable. In particular, the characteristics in a high humidity atmosphere are excellent.

  In order to obtain the above effect, a synergistic effect between the polyanion and the dispersant having a branched structure is necessary. In the case of only the polyanion, the obtained conductive polymer material may have low conductivity and inferior water resistance for the above reasons. In the case of only a dispersing agent having a branched structure, since there is no polyanion that can be doped into the conductive polymer, the resulting conductive organic material has low conductivity. In the case of a dispersant having a polyanion and a linear structure, the dispersion stability of the particles in the desired conductive polymer suspension solution may not be obtained. The dispersant needs to be blended in a large amount with respect to the conductive polymer, and the obtained conductive polymer material may have low conductivity and poor water resistance.

  The above effect is obtained when the conductive polymer suspension solution contains a conductive polymer having a particle size of 100 nm or less, that is, a part of the conductive polymer contained in the conductive polymer suspension solution or This is particularly noticeable when the total particle size is 100 nm or less. Usually, when some or all of the particles in the conductive polymer suspension solution have a particle diameter of 100 nm or less, the polyanion has a high conductivity for stabilizing the dispersion of the particles in the conductive polymer suspension solution. More conductive molecules are required for the molecules, and the conductive organic material obtained from the conductive polymer suspension has a particularly low conductivity. However, with the above configuration, it is not necessary to increase the polyanion even when part or all of the particles in the conductive polymer suspension solution have a particle diameter of 100 nm or less. The conductive organic material obtained from is high conductivity.

  A conductive polymer suspension solution in which a part or all of the conductive polymer has a particle size of 100 nm or less is conductive inside the porous pores of the anode conductor made of a valve metal having an average pore size of 1000 nm or less. Suitable for forming a conductive polymer material. It is particularly preferable if the conductive polymer material has a high conductivity.

  The average particle diameter of the conductive polymer (particles) contained in the conductive polymer suspension is preferably in the range of 1 to 1000 nm. As described above, the conductive polymer having a particle diameter of 100 nm or less is used. More preferably it is included.

  The conductive polymer contained in the conductive polymer suspension is preferably a conductive organic polymer as a polymer composed of at least one of pyrrole, thiophene, and derivatives thereof. The molecular weight and characteristics of the conductive polymer can be selected in accordance with the application. For an electrolytic capacitor, a molecular weight and a characteristic range suitable for the configuration of the electrolytic capacitor may be selected. Among them, poly (3,4-ethylenedioxythiophene) having a structural unit represented by the following formula (1) or a derivative thereof is preferable as the conductive polymer. The conductive polymer may be a homopolymer, a copolymer, one type, or two or more types.

  The content of the conductive polymer in the conductive polymer suspension solution is preferably 0.1 to 30 parts by weight, preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of water as the solvent. Is more preferable.

  The conductive polymer suspension contains a polyanion. Examples of the polyanion include polycarboxylic acids such as polyacrylic acid, polymethacrylic acid, and polymaleic acid; polysulfonic acids such as polyvinyl sulfonic acid and polystyrene sulfonic acid; and copolymers having at least one of these structural units. Among these, polystyrene sulfonic acid having a structural unit represented by the following (2) is preferable. One or more polyanions may be used.

  The weight average molecular weight of the polyanion is preferably 2,000 to 500,000, and more preferably 10,000 to 200,000.

  The conductive polymer suspension solution preferably contains a dispersant having a branched structure together with the polyanion. The dispersant having a branched structure may be one type or two or more types.

  A dispersant with a branched structure is an organic polymer dispersion that has an adsorbing group for adsorbing to a conductive polymer in the main chain and one or more hydrophilic and / or hydrophobic side chains. An agent is more preferable.

  Examples of the main chain of the dispersant include polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, acrylic resin, and a copolymer having these structural units.

  Examples of the adsorption group possessed by the main chain of the dispersant include a carboxyl group, a sulfo group, a phosphate group, and an amino group. A carboxyl group or a sulfo group is particularly desirable because of its high adsorptivity to the conductive polymer.

  Examples of the side chain of the dispersant include hydrophilic polyether, polyvinyl alcohol, polyvinyl pyrrolidone, and hydrophobic polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, and acrylic resin. One side chain may be used, but it is particularly preferable to have a plurality of side chains because steric hindrance increases and the effect of improving the dispersibility of the particles increases. One type of side chain may be used, or two or more types may be used. It is particularly preferred to have both a hydrophilic side chain and a hydrophobic side chain because the stability of the particles in the conductive polymer suspension and the strength of the conductive polymer material are increased.

  The dispersant having a branched structure can be selected from those used as a dispersant for solid particles such as pigments from the above-mentioned dispersant having a branched structure. A dispersant commercially available as “DISPERBYK-190” used in each example can be suitably used.

  “DISPERBYK-190” has an acrylic resin as a main chain, and the main chain has a carboxyl group as an adsorbing group. In addition, the side chain has a plurality of hydrophilic polyethers and hydrophobic polystyrenes, and is a dispersant having a branched structure.

  The content of the polyanion and the dispersant having a branched structure in the conductive polymer suspension is 10 to 200 parts by weight of the polyanion with respect to 100 parts by weight of the conductive polymer, and the dispersant has a branched structure. Is preferably 1 to 120 parts by weight. More preferably, the polyanion is 50 to 150 parts by weight and the dispersant having a branched structure is 1 to 50 parts by weight with respect to 100 parts by weight of the conductive polymer.

  The conductive polymer suspension solution preferably contains one or more water-soluble binders. Examples of the water-soluble binder include polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinyl pyrrolidone, polyester, polyurethane, polyamide, and copolymers having these structural units, which are used for coating polymer suspensions. You can select from the available items. Among them, the polyester or polyamide modified to be water-soluble by addition of a carboxyl group or a sulfo group or copolymerization with polyethylene glycol does not impair the dispersion stability of the particles in the conductive polymer suspension solution. It has been found that the conductive organic material obtained from the conductive polymer suspension solution hardly loses conductivity.

  The content of the water-soluble binder in the conductive polymer suspension is 10 to 400 parts by weight of the water-soluble binder with respect to 100 parts by weight of the conductive polymer.

  By adding a water-soluble binder, the adhesion to the substrate is improved. The conductive polymer suspension may contain a crosslinking agent that crosslinks the water-soluble binder together with the water-soluble binder.

  It is preferable to mix erythritol and / or pentaerythritol with the conductive polymer suspension for the purpose of improving the conductivity, density and strength characteristics of the conductive polymer material.

  Since erythritol has higher crystallinity than polyhydric alcohols such as sorbitol and maltose, it is preferable from the viewpoint of low hygroscopicity and easy handling. In addition, erythritol is known as a food additive used as a sweetener, and is excellent in safety and stability, and in terms of solubility in water, for example, compared to non-aqueous solvents such as ethylene glycol and glycerin. In addition, there is an advantage that the degree of freedom in design of the addition amount is high several times.

  Pentaerythritol has the characteristic of gradually subliming when heated and dehydrating and polymerizing when heated above its melting point. This has the advantage that the physical properties of the conductive polymer material change, and the density and strength are improved. Such reactivity is attributed to its chemical structure, and is unlikely to occur with chemical structures such as erythritol and sorbitol.

  The effect of improving the conductivity is high for erythritol, and the effect of improving the characteristics of density and strength is high for pentaerythritol.

  The effect is obtained by mixing at least one of erythritol and pentaerythritol in the conductive polymer suspension solution at a concentration equal to or higher than the polymer concentration in the conductive polymer suspension solution. The upper limit concentration of the addition amount is not particularly limited as long as it is an amount that can be dissolved in the conductive polymer suspension solution.

  The conductive polymer material according to the present embodiment is obtained by drying the above-described conductive polymer suspension solution and removing the solvent. The conductive polymer material has excellent adhesion and water resistance to the substrate, and has high conductivity. It is. The drying temperature for removing the solvent is not particularly limited as long as it is equal to or lower than the decomposition temperature of the conductive polymer, but is preferably 300 ° C. or lower.

<Method for producing conductive polymer suspension solution>
The manufacturing method of the conductive polymer suspension according to the present embodiment includes the following steps.

[First step]
In the present embodiment, first, a monomer containing a conductive polymer is chemically oxidatively polymerized using an oxidizing agent in a solvent containing an organic acid or a salt thereof as a dopant to obtain a mixture containing the conductive polymer. . In the first step, a conductive polymer having a high degree of polymerization and a high degree of crystallization can be obtained.

  Examples of the dopant include alkyl sulfonic acid, benzene sulfonic acid, naphthalene sulfonic acid, anthraquinone sulfonic acid, camphor sulfonic acid and derivatives thereof, and salts thereof such as iron (III). These sulfonic acids may be monosulfonic acid, disulfonic acid or trisulfonic acid. Examples of alkylsulfonic acid derivatives include 2-acrylamido-2-methylpropanesulfonic acid. Examples of benzenesulfonic acid derivatives include phenolsulfonic acid, styrenesulfonic acid, toluenesulfonic acid, and dodecylbenzenesulfonic acid. Examples of naphthalene sulfonic acid derivatives include 1-naphthalene sulfonic acid, 2-naphthalene sulfonic acid, 1,3-naphthalene disulfonic acid, 1,3,6-naphthalene trisulfonic acid, and 6-ethyl-1-naphthalene sulfonic acid. It is done. Examples of the derivatives of anthraquinone sulfonic acid include anthraquinone-1-sulfonic acid, anthraquinone-2-sulfonic acid, anthraquinone-2,6-disulfonic acid, and 2-methylanthraquinone-6-sulfonic acid. Among these, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 1,3,6-naphthalenetrisulfonic acid, anthraquinone disulfonic acid, p-toluenesulfonic acid, camphorsulfonic acid or iron (III) salts thereof are preferable. Camphorsulfonic acid is more preferable because it has a great influence on the high crystallization of the polymer. Camphorsulfonic acid may be an optically active substance. 1 type may be sufficient as a dopant and 2 or more types may be sufficient as it.

  The amount of the dopant used is not particularly limited because it can be removed in the second step even if it is excessive, but it is preferably 1 to 100 parts by weight with respect to 1 part by weight of the monomer, and 1 to 50 parts by weight. Is more preferable.

  The solvent may be water, an organic solvent, or a water-miscible organic solvent, preferably a solvent having good compatibility with the monomer, and particularly preferably a solvent having good compatibility with the dopant and the oxidizing agent. Examples of the organic solvent include alcohol solvents such as methanol, ethanol and propanol; and low polar solvents such as acetonitrile, acetone and dimethyl sulfoxide. 1 type may be sufficient as an organic solvent, and 2 or more types may be sufficient as it. Of these, ethanol or a mixed solvent of ethanol and water is preferable.

  As the conductive polymer, a polymer composed of at least one of pyrrole, thiophene and derivatives thereof is preferable.

  The monomer that provides the conductive polymer may be selected according to the target conductive polymer. The monomer may be one type or two or more types.

  Polypyrrole and its derivatives are obtained by polymerizing the corresponding pyrrole or a derivative of pyrrole. As derivatives of pyrrole, 3-alkyl pyrrole such as 3-hexyl pyrrole, 3,4-dialkyl pyrrole such as 3,4-dihexyl pyrrole, 3-alkoxy pyrrole such as 3-methoxy pyrrole, 3,4-dimethoxy pyrrole, etc. 3,4-dimethoxypyrrole.

  Polythiophene and derivatives thereof are obtained by polymerizing the corresponding thiophene or a derivative of thiophene. Examples of thiophene derivatives include 3,4-ethylenedioxythiophene and derivatives thereof, 3-alkylthiophenes such as 3-hexylthiophene, and 3-alkoxythiophenes such as 3-methoxythiophene. Examples of 3,4-ethylenedioxythiophene derivatives include 3,4- (1-alkyl) ethylenedioxythiophene such as 3,4- (1-hexyl) ethylenedioxythiophene.

  Among these, poly (3,4-ethylenedioxythiophene) represented by the following formula (3) or a derivative thereof is preferable.

  The concentration of the monomer in the solvent is preferably 0.1 to 50% by weight, and more preferably 0.5 to 30% by weight.

  The oxidizing agent is not particularly limited, and iron (III) chloride hexahydrate, anhydrous iron (III) chloride, iron (III) nitrate nonahydrate, anhydrous ferric nitrate, iron (III) sulfate n water Japanese (n = 3-12), iron (III) sulfate dodecahydrate, iron (III) perchlorate n hydrate (n = 1,6), iron (III) tetrafluoroborate, etc. Iron (III) salts of inorganic acids of copper; copper (II) salts of inorganic acids such as copper (II) chloride, copper (II) sulfate, copper (II) tetrafluoroborate; nitrosonium tetrafluoroborate; ammonium persulfate Persulfates such as sodium persulfate and potassium persulfate; periodates such as potassium periodate; hydrogen peroxide, ozone, potassium hexacyanoferrate (III), tetraammonium cerium sulfate (IV) dihydrate , Bromine, iodine; p-toluenesulfo Iron (III) salts of organic acids, iron (III), or the like can be used. Among these, inorganic acid or organic acid iron salt (III) or persulfate is preferable, ammonium persulfate or iron p-toluenesulfonate (III) is more preferable, and p has the property of serving as a dopant. -More preferred is iron (III) toluenesulfonate. 1 type may be sufficient as an oxidizing agent, and 2 or more types may be sufficient as it.

  The amount of the oxidizing agent used is not particularly limited because it can be removed in the second step even if it is excessive, but in order to obtain a high conductivity polymer by reacting in a milder oxidizing atmosphere, 0.5 to 100 parts by weight is preferable with respect to 1 part by weight of the monomer, and 1 to 50 parts by weight is more preferable.

  The reaction temperature of chemical oxidative polymerization is not particularly limited, but is generally near the reflux temperature of the solvent used, preferably 0 to 100 ° C, more preferably 10 to 50 ° C. If the reaction temperature is not appropriate, the conductivity may be impaired. The reaction time of chemical oxidative polymerization is about 5 to 100 hours, although it depends on the type and amount of oxidant, reaction temperature, stirring conditions and the like.

  The first step is preferably performed in the presence of a substance having a surface active action. As the substance having a surface active action, an anionic surfactant, a cationic surfactant, and an amphoteric surfactant can be used, and dodecylbenzenesulfonic acid, polyethylene glycol, and the like are preferable.

[Second step]
In this embodiment, the conductive polymer is recovered from the mixture obtained in the first step. Specifically, by separating and washing the conductive polymer from the reaction liquid containing the conductive polymer obtained by chemical oxidative polymerization, dopants, unreacted monomers, residual metal ions and anions derived from the oxidizing agent Remove. By the second step, sufficient purification treatment is possible, and a highly pure conductive polymer can be obtained.

  Examples of the method for separating the conductive polymer from the reaction solution include a filtration method and a centrifugal separation method.

  The washing solvent is preferably performed using a solvent capable of dissolving the monomer and / or the oxidizing agent without dissolving the conductive polymer. Examples of the cleaning solvent include water and alcohol solvents such as methanol, ethanol, and propanol. The cleaning solvent may be one type or two or more types. The degree of washing can be confirmed by performing pH measurement and colorimetric observation of the washing solvent after washing.

  Furthermore, since the metal component derived from the oxidizing agent can be removed to a higher degree, it is preferable to wash the conductive polymer and / or heat-treat the conductive polymer. The temperature of the heat treatment is not particularly limited as long as it is equal to or lower than the decomposition temperature of the conductive polymer, but is preferably performed at less than 300 ° C. In addition, performing an ion exchange treatment using an ion exchange resin is also effective as a method for removing metal ions and anions derived from an oxidizing agent.

  Impurities contained in the conductive polymer can be quantified by ICP emission analysis or ion chromatography.

[Third step]
In this embodiment, an oxidizing agent is mixed with the conductive polymer recovered in the second step in an aqueous solvent containing a polyanion. In the third step, a conductive polymer suspension solution with good dispersibility of the conductive polymer is obtained by allowing the polyanion as a dispersant and the oxidizing agent to act on the conductive polymer. As a dispersion mechanism, at least a doping action of anions derived from polyanions can be considered.

  As the polyanion, the aforementioned polyanions can be used. Of these, polystyrene sulfonic acid is preferable. The weight average molecular weight of the polyanion is preferably 2,000 to 500,000, and more preferably 10,000 to 200,000.

  The amount of polyanion used is preferably 10 to 200 parts by weight, more preferably 50 to 150 parts by weight, based on 100 parts by weight of the conductive polymer obtained in the second step.

  As the oxidizing agent, the same oxidizing agent used in the first step can be used, and among them, ammonium persulfate or hydrogen peroxide is preferable.

  The amount of the oxidizing agent used is preferably 10 to 500 parts by weight, more preferably 50 to 300 parts by weight, based on 100 parts by weight of the conductive polymer obtained in the second step.

  As the aqueous solvent, water is preferable, but there is no problem even if a water-soluble organic solvent is added. As the water-soluble organic solvent, a solvent suitable for an oxidation reaction can be selected and used when added to water. In addition to these requirements, when the liquid mixture obtained in the third step is used as it is in the fourth step, it is used as a solvent (liquid medium) for the finally obtained conductive polymer suspension. It is preferable to select and use an organic solvent that can be used. Examples of such an organic solvent include alcohol solvents such as methanol, ethanol and propanol; and low polar solvents such as acetonitrile, acetone and dimethyl sulfoxide. 1 type may be sufficient as an organic solvent, and 2 or more types may be sufficient as it.

  The reaction temperature in the third step is not particularly limited, but is preferably 0 to 100 ° C, more preferably 10 to 50 ° C. The reaction time is not particularly limited, but is about 5 to 100 hours. Moreover, it is preferable to perform the ion exchange process mentioned above after a 3rd process.

[Fourth step]
In this embodiment, the conductive polymer is pulverized after mixing the dispersant having a branched structure. After mixing the dispersing agent having a branched structure, the conductive polymer is pulverized to obtain a conductive polymer suspension having high dispersion stability. By the pulverization in the fourth step, at least part of the conductive polymer, that is, part or all of the conductive polymer can be pulverized to 100 nm or less.

  The amount of the dispersant having a branched structure is preferably 1 to 120 parts by weight, preferably 1 to 50 parts by weight, based on 100 parts by weight of the conductive polymer obtained in the second step. Is more preferable.

  It is preferable to mix one or more water-soluble binders during or after the fourth step. As the water-soluble binder, the aforementioned binder can be used. Of these, polyesters or polyamides modified to be water-soluble by addition of carboxyl groups or sulfo groups are particularly preferred.

  The content of the water-soluble binder in the conductive polymer suspension is 10 to 400 parts by weight of the water-soluble binder with respect to 100 parts by weight of the conductive polymer.

  It is preferable to mix erythritol and / or pentaerythritol during or after the fourth step. The amount of erythritol and pentaerythritol added is effective when mixed at a concentration equal to or higher than the polymer concentration in the conductive polymer suspension solution. The upper limit concentration of the addition amount is not particularly limited as long as it is an amount that can be dissolved in the conductive polymer suspension solution.

<Electrolytic capacitor and manufacturing method thereof>
The electrolytic capacitor according to the present embodiment has a conductive polymer material obtained from the conductive polymer suspension solution as an electrolyte layer. The electrolyte layer is preferably solid. In the electrolytic capacitor according to the present embodiment, since the material forming the electrolyte has high conductivity, the electrolytic capacitor has a low ESR. In addition, polymer materials with high crystallinity are also highly correlated with oxygen barrier properties, and due to the effect of the binder, the adhesion to the substrate is excellent, so it is expected that the reliability of electrolytic capacitors will be improved It is.

  FIG. 1 is a schematic cross-sectional view showing the structure of the solid electrolytic capacitor according to the present embodiment. This electric field capacitor has a structure in which a dielectric layer 2, a solid electrolyte layer 3, and a cathode conductor 4 are formed in this order on an anode conductor 1.

  The anode conductor 1 is formed of a valve metal plate, foil, or wire; a sintered body made of fine particles of the valve metal; a porous metal that has been subjected to surface expansion treatment by etching. Examples of the valve action metal include tantalum, aluminum, titanium, niobium, zirconium, and alloys thereof. Among these, at least one valve action metal selected from aluminum, tantalum and niobium is preferable.

  The dielectric layer 2 is a layer that can be formed by electrolytic oxidation of the surface of the anode conductor 1, and is also formed in pores such as a sintered body and a porous body. The thickness of the dielectric layer 2 can be adjusted as appropriate by the voltage of electrolytic oxidation.

  The solid electrolyte layer 3 contains the conductive polymer suspension or the conductive organic material. The solid polymer electrolyte layer 3 may have a single layer structure or a multilayer structure. In the solid electrolytic capacitor shown in FIG. 1, the solid polymer electrolyte layer 3 is composed of a first conductive polymer compound layer 3A and a second conductive polymer compound layer 3B.

  The solid electrolyte layer 3 further comprises a conductive polymer obtained by polymerizing pyrrole, thiophene, aniline or a derivative thereof; an oxide derivative such as manganese dioxide or ruthenium oxide; TCNQ (7,7,8,8-tetracyano) An organic semiconductor such as quinodimethane complex salt) may be contained.

  Examples of the method for forming the solid electrolyte layer 3 include a method of applying or impregnating the conductive polymer suspension solution on the dielectric layer 2 and removing the solvent from the conductive polymer suspension solution. Further, the solid electrolyte layer 3 in the solid electrolytic capacitor shown in FIG. 1 is obtained by chemical oxidation polymerization or electrolytic polymerization of a monomer that gives the first conductive polymer compound on the dielectric layer. The layer 3A is formed, and the first conductive polymer compound layer 3A is coated or impregnated with the above-described conductive polymer suspension solution to form a second conductive polymer compound layer. can do.

  As a monomer that gives the first conductive polymer compound, at least one selected from pyrrole, thiophene, aniline, and derivatives thereof can be used. The dopant used when the monomer is chemically oxidatively polymerized or electrolytically polymerized to obtain the first conductive polymer compound includes benzenesulfonic acid, naphthalenesulfonic acid, phenolsulfonic acid, styrenesulfonic acid, and derivatives thereof. Acid compounds are preferred. The molecular weight of the dopant can be appropriately selected from low molecular weight compounds to high molecular weight compounds. As the solvent, only water or a mixed solvent containing water and an organic solvent soluble in water may be used.

  The method of application or impregnation is not particularly limited, but it is preferably left for several minutes to several tens of minutes after application or impregnation in order to sufficiently fill the porous polymer pores with the conductive polymer suspension. . Repeated immersion, reduced pressure method or pressurized method is preferred.

  The removal of the solvent from the conductive polymer suspension can be performed by drying the conductive polymer. The drying temperature is not particularly limited as long as the solvent can be removed, but the upper limit temperature is preferably less than 300 ° C. from the viewpoint of preventing element deterioration due to heat. The drying time must be appropriately optimized depending on the drying temperature, but is not particularly limited as long as the conductivity is not impaired.

  The cathode conductor 4 is not particularly limited as long as it is a conductor. For example, the cathode conductor 4 can have a two-layer structure including a carbon layer 5 such as graphite and a silver conductive resin 6.

Hereinafter, the present embodiment will be described more specifically based on examples, but the present embodiment is not limited to only these examples. Examples 1 to 4 and 8 to 11 are reference examples.

[Example 1]
(First step)
As a solvent, 3,4-ethylenedioxythiophene (2 g) as a monomer, camphorsulfonic acid (2 g) as a dopant, and iron (III) p-toluenesulfonate (18 g) functioning as an oxidizing agent and a dopant. In ethanol (60 ml). The resulting solution was stirred at room temperature for 24 hours to oxidize the monomer. At this time, the mixture changed from yellow to dark blue.

(Second step)
The mixed liquid obtained in the first step was filtered with a vacuum filtration device to recover the powder. The obtained powder was washed with pure water to remove excess oxidizing agent / dopant. Washing with pure water was repeated until the pH of the filtrate was 6-7. After the pH of the filtrate reached 6-7, it was further washed with ethanol to remove the monomer, the oxidizing agent and the oxidizing agent after reaction (iron (II) -toluenesulfonate). Washing with ethanol was performed until the color of the filtrate became colorless and transparent.

(Third process)
After the powder (1 g) washed in the second step was dispersed in water (200 ml), a 20% by weight aqueous solution (0 0.5 g) was added. To this mixture, ammonium persulfate (1.5 g) as an oxidizing agent was further added, and the mixture was stirred at room temperature for 24 hours. The resulting polythiophene suspension was dark blue.

(Fourth process)
To the mixed solution obtained in the third step, a dispersant having a branched structure (DISPERBYK (registered trademark) -190, 40 wt% aqueous solution, BYK-Chemie GmbH) (3 g) is added, and 1 at room temperature. Stir for hours to dissolve completely. Thereafter, particles in the mixed solution were pulverized using a bead mill, and the average particle size was set to 500 nm. The resulting polythiophene suspension maintained a dark blue color.
For measurement of the average particle size, a dynamic light scattering method (measuring device: zeta potential / particle size measurement system ELSZ-2 (Otsuka Electronics Co., Ltd.)) was used.

(Evaluation of polythiophene suspension)
100 μl of the obtained polythiophene suspension was dropped on a glass substrate, and the solvent was completely evaporated in a thermostatic bath at 125 ° C. to dry, thereby forming a conductive polymer film.

  The resulting conductive polymer film was measured for surface resistance (Ω / □) and film thickness by the four probe method, and the conductivity (S / cm) was calculated.

[Example 2]
In the third step, the addition amount of a 20% by weight aqueous solution of polystyrene sulfonic acid (weight average molecular weight: 50,000) is (5 g), and in the fourth step, a dispersant having a branched structure (DISPERBYK®) -A polythiophene suspension was prepared in the same manner as in Example 1 except that the amount of 190, 40 wt% aqueous solution (BYK-Chemie GmbH) was changed to (0.2 g). And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 3
In the third step, the addition amount of a 20% by weight aqueous solution of polystyrene sulfonic acid (weight average molecular weight: 50,000) is (10 g), and in the fourth step, a dispersant having a branched structure (DISPERBYK®) -A polythiophene suspension was prepared in the same manner as in Example 1 except that the amount of 190, 40 wt% aqueous solution (BYK-Chemie GmbH) was changed to (0.04 g). And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 4
In the third step, a polythiophene suspension was produced in the same manner as in Example 2 except that polystyrene sulfonic acid having a weight average molecular weight of 2,000 was used as the polyacid. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 5
In the fourth step, a polythiophene suspension was produced in the same manner as in Example 1 except that the particles in the mixed solution were pulverized using a bead mill and the average particle size was 50 nm. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 6
In the fourth step, a polythiophene suspension was produced in the same manner as in Example 2 except that the particles in the mixed solution were pulverized using a bead mill and the average particle size was 50 nm. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 7
In the fourth step, a polythiophene suspension was produced in the same manner as in Example 3 except that the particles in the mixed solution were pulverized using a bead mill and the average particle size was 50 nm. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 8
After the fourth step, a water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) was added, and a step of stirring at room temperature for 1 hour to completely dissolve was added. A polythiophene suspension was produced in the same manner as in Example 2 except for the above. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 9
After the fourth step, a step of adding water-soluble polyamide (AQ nylon P-95, 50% by weight aqueous solution, Toray Industries, Inc.) (4 g) and stirring for 1 hour at room temperature for complete dissolution was added. A polythiophene suspension was produced in the same manner as in Example 2 except for the above. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 10
After the fourth step, water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) and erythritol (10 g) were added and stirred at room temperature for 1 hour to complete A polythiophene suspension solution was produced in the same manner as in Example 2 except that the step of dissolving in was added. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 11
After the fourth step, water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) and pentaerythritol (10 g) were added and stirred at room temperature for 1 hour. A polythiophene suspension solution was produced in the same manner as in Example 2 except that a step of complete dissolution was added. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 12
After the fourth step, a water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) was added, and a step of stirring at room temperature for 1 hour to completely dissolve was added. A polythiophene suspension was prepared in the same manner as in Example 6 except that. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 13
After the fourth step, a step of adding water-soluble polyamide (AQ nylon P-95, 50% by weight aqueous solution, Toray Industries, Inc.) (4 g) and stirring for 1 hour at room temperature for complete dissolution was added. A polythiophene suspension was prepared in the same manner as in Example 6 except that. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 14
After the fourth step, water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) and erythritol (10 g) were added and stirred at room temperature for 1 hour to complete A polythiophene suspension solution was produced in the same manner as in Example 6 except that a step of dissolving in was added. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

Example 15
After the fourth step, water-soluble polyester (Pesresin A-610, 25% by weight aqueous solution, Takamatsu Yushi Co., Ltd.) (8 g) and pentaerythritol (10 g) were added and stirred at room temperature for 1 hour. A polythiophene suspension was produced in the same manner as in Example 6 except that a step of complete dissolution was added. And except having used the obtained polythiophene suspension solution, it carried out similarly to Example 1, formed the conductive polymer film, and evaluated the electrical conductivity. The results are shown in Table 1.

[Comparative Example 1]
A polythiophene suspension was produced by the method described in Example 1 of Patent Document 1. Specifically, polystyrene sulfonic acid (2 g) having a weight average molecular weight of 4,000, 3,4-ethylenedioxythiophene (0.5 g) and iron (III) sulfate (0.05 g) are dissolved in water (20 ml). And air was introduced over 24 hours to produce a polythiophene suspension.

  A conductive polymer film was formed in the same manner as in Example 1 except that the obtained polythiophene suspension was used, and the conductivity was evaluated. The results are shown in Table 1.

[Comparative Example 2]
Polystyrene sulfonic acid (12.4 g) having a weight average molecular weight of 4,000, 3,4-ethylenedioxythiophene (1.6 g) and iron (III) sulfate (0.16 g) were dissolved in water (1000 ml), and 24 Air was introduced over time to produce a polythiophene suspension. Thereafter, it was homogenized twice using a high-pressure homogenizer at 700 bar and a nozzle diameter of 0.1 mm. The average particle size of the particles in the aqueous solution was 20 nm.

  A conductive polymer film was formed in the same manner as in Example 1 except that the obtained polythiophene suspension was used, and the conductivity was evaluated. The results are shown in Table 1.

Example 16
Porous aluminum was used as an anode conductor made of a valve metal, and an oxide film serving as a dielectric layer was formed on the surface of the aluminum by anodic oxidation. The anode part and the cathode part were separated by an insulating resin. Next, the cathode part of the anode conductor on which the dielectric layer is formed is dipped in the polythiophene suspension prepared in Example 2 and pulled up, and then dried and solidified in a constant temperature bath at 125 ° C. to form a solid electrolyte layer. did. And a graphite layer and a silver content resin layer were formed in order on the solid electrolyte layer, and the solid electrolytic capacitor was manufactured.

The capacity and ESR (equivalent series resistance) of the obtained solid electrolytic capacitor were measured using an LCR meter at frequencies of 120 Hz and 100 kHz, respectively. The values of the capacity and ESR were normalized to the unit area (1 cm ² ) of the total cathode area. The results are shown in Table 2.

Example 17
A solid electrolytic capacitor was produced in the same manner as in Example 16 except that the polythiophene suspension solution produced in Example 10 was used for forming the solid electrolyte layer, and its capacity and ESR were evaluated. The results are shown in Table 2.

Example 18
A solid electrolytic capacitor was produced in the same manner as in Example 16 except that the polythiophene suspension solution produced in Example 14 was used for forming the solid electrolyte layer, and its capacity and ESR were evaluated. The results are shown in Table 2.

Example 19
Porous aluminum was used as an anode conductor made of a valve metal, and an oxide film serving as a dielectric layer was formed on the surface of the aluminum by anodic oxidation. The anode part and the cathode part were separated by an insulating resin. Next, the cathode part of the anode conductor on which the dielectric layer was formed was mixed with a monomer solution obtained by dissolving pyrrole (10 g) in pure water (200 ml), p-toluenesulfonic acid (20 g) as a dopant, and excess as an oxidizing agent. A first conductive polymer compound layer was formed by repeating immersion and pulling up 10 times sequentially with an oxidizing agent solution in which ammonium sulfate (10 g) was dissolved in pure water (200 ml), and performing chemical oxidative polymerization. .

  The polythiophene suspension produced in Example 10 is dropped on the first conductive polymer compound layer, and dried and solidified in a constant temperature bath at 125 ° C. to form a second conductive polymer compound layer. did. Then, a solid electrolytic capacitor was manufactured by sequentially forming a graphite layer and a silver-containing resin layer on the solid electrolyte layer composed of the first conductive polymer compound layer and the second conductive polymer compound layer. .

  The capacity and ESR of the obtained solid electrolytic capacitor were evaluated in the same manner as in Example 16. The results are shown in Table 2.

Example 20
A solid electrolytic capacitor was produced in the same manner as in Example 19 except that the polythiophene suspension solution produced in Example 14 was used for forming the solid electrolyte layer. The capacity and ESR of the obtained solid electrolytic capacitor were evaluated in the same manner as in Example 16. The results are shown in Table 2.

[Comparative Example 3]
A solid electrolytic capacitor was produced in the same manner as in Example 16 except that the polythiophene suspension solution produced in Comparative Example 1 was used instead of the polythiophene suspension solution produced in Example 2. The capacity and ESR of the obtained solid electrolytic capacitor were evaluated in the same manner as in Example 16. The results are shown in Table 2.

[Comparative Example 4]
A solid electrolytic capacitor was produced in the same manner as in Example 16 except that the polythiophene suspension solution produced in Comparative Example 2 was used instead of the polythiophene suspension solution produced in Example 2. The capacity and ESR of the obtained solid electrolytic capacitor were evaluated in the same manner as in Example 16. The results are shown in Table 2.

In Table 1, when the average particle size is 500 nm, particles having a particle size of 100 nm or less are not included.

  As shown in Table 1, the conductive polymer films obtained in Examples 1 to 15 had higher conductivity than the conductive polymer films obtained in Comparative Examples 1 and 2. That is, the effect of increasing the conductivity according to the present embodiment is clear. In particular, even when a part or all of the conductive polymer in the conductive polymer suspension solution has a particle size of 100 nm or less (when the average particle size is 50 nm), a highly conductive conductive polymer film is formed. Obtained and the effect is remarkable.

  The effect of increasing the electrical conductivity is that the conductive polymer suspension solution according to this embodiment contains a conductive polymer, at least one polyanion, and at least one dispersant having a branched structure. It is to do.

  By setting it as the said structure, a conductive polymer suspension solution is excellent in the dispersion stability of the particle | grains to contain. Therefore, undoped polyanions, that is, polyanions that do not contribute to conductivity can be reduced with respect to the conductive polymer, and the conductive organic material obtained from the conductive polymer suspension solution has high conductivity. is there.

  The conductive polymer films obtained in Examples 2, 4, 6, 8 to 15 had higher conductivity than the conductive polymer films obtained in Examples 1, 3, 5, and 7. This is because the ratio of the polyanion and the dispersant having a branched structure contained in the conductive polymer suspension solutions of Examples 2, 4, 6, 8 to 15 to the conductive polymer is This is because it is smaller than the conductive polymer suspension solutions of 1, 3, 5, and 7.

  In addition, in the method for producing a conductive polymer suspension solution, the first step to the third step are performed, so that (1) a dopant that increases the crystallinity can be selected because of a wide range of dopant options. (2) The degree of polymerization can be increased because a solvent structure highly compatible with the monomer can be selected, and (3) high purity can be achieved because of easy cleaning, and as a result, high conductivity can be achieved. Can be planned.

  Furthermore, the conductivity is improved by adding erythritol during or after the fourth step. This is because erythritol interacts with the undoped dopant anion (resistance component) introduced in the third step, which is present in the vicinity of the conductive polymer particles in the conductive polymer suspension solution. This is because the resistance between the polymer particles is lowered and the density of the conductive polymer is increased.

  Even if a water-soluble binder made of polyester or polyamide is added during or after the fourth step, the conductivity is hardly impaired.

  As shown in Table 2, the solid electrolytic capacitors obtained in Examples 16 to 20 had lower resistance (ESR) than the solid electrolytic capacitors obtained in Comparative Examples 3 to 4. In Examples 16 to 20, since the conductivity of the conductive organic material used is high, the resistance of the solid electrolyte can be reduced, and the resistance (ESR) can be reduced. Even when a part or all of the conductive polymer in the conductive polymer suspension solution has a particle diameter of 100 nm or less, a solid electrolytic capacitor having a low resistance (ESR) is obtained, and the effect is remarkable. In addition, a conductive polymer suspension solution in which a part or all of the conductive polymer has a particle diameter of 100 nm or less forms a conductive organic material in the porous pores of the anode conductor made of a valve metal. And the appearance of capacity is excellent.

1 Anode conductor 2 Dielectric layer 3 Solid electrolyte layer 3A First conductive polymer compound layer 3B Second conductive polymer compound layer 4 Cathode conductor 5 Carbon layer 6 Silver conductive resin layer

Claims (30)

Containing a conductive polymer, at least one polyanion, and at least one dispersant having a branched structure;
The conductive polymer includes a conductive polymer having a particle size of 100 nm or less,
The dispersant having the branched structure has an adsorption group for adsorbing to the conductive polymer in the main chain, and has one or more hydrophilic side chains and one or more hydrophobic side chains. Consisting of a structure
The main chain is selected from polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, acrylic resin and a copolymer having these structural units,
The adsorbing group is selected from a carboxyl group, a sulfo group, a phosphate group and an amino group,
The side chain has a hydrophilic side chain and a hydrophobic side chain, and the hydrophilic side chain is selected from polyether, polyvinyl alcohol and polyvinyl pyrrolidone, and the hydrophobic side chain is polyethylene. Selected from polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate and acrylic resin ,
The conductive polymer comprising 10 to 200 parts by weight of the polyanion and 1 to 120 parts by weight of the dispersant having the branched structure with respect to 100 parts by weight of the conductive polymer. Suspension solution.   The conductive polymer suspension solution according to claim 1, wherein a particle diameter of the conductive polymer is 100 nm or less. The conductive polymer suspension solution according to claim 1 or 2 , wherein the conductive polymer is a polymer composed of at least one of pyrrole, thiophene, and derivatives thereof. The conductive polymer suspension solution according to any one of claims 1 to 3 , wherein the polyanion contains polystyrene sulfonic acid. The conductive polymer suspension according to claim 4 , wherein the polystyrenesulfonic acid has a weight average molecular weight of 2,000 to 500,000. The conductive polymer suspension solution according to any one of claims 1 to 5 , comprising at least one water-soluble binder. The conductive polymer suspension solution according to claim 6 , wherein the water-soluble binder is at least one of polyester and polyamide. The conductive polymer suspension solution according to claim 6 or 7 , wherein at least one of the water-soluble binders is 10 to 400 parts by weight with respect to 100 parts by weight of the conductive polymer. Erythritol and / or a conductive polymer suspension according to any one of claims 1 to 8, characterized in that it comprises pentaerythritol. A first step of obtaining a mixture containing a conductive polymer by chemically oxidatively polymerizing a monomer which gives a conductive polymer in a solvent containing an organic acid or a salt thereof as a dopant using an oxidizing agent;
A second step of recovering the conductive polymer from the mixture;
A third step of mixing an oxidizing agent with the conductive polymer in an aqueous solvent containing a polyanion;
A fourth step of pulverizing the conductive polymer so as to include a conductive polymer having a particle diameter of 100 nm or less after mixing the dispersant having a branched structure;
The dispersant having the branched structure has an adsorption group for adsorbing to the conductive polymer in the main chain, and has one or more hydrophilic side chains and one or more hydrophobic side chains. Consisting of a structure
The main chain is selected from polyethylene, polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, acrylic resin and a copolymer having these structural units,
The adsorbing group is selected from a carboxyl group, a sulfo group, a phosphate group and an amino group,
The side chain has a hydrophilic side chain and a hydrophobic side chain, and the hydrophilic side chain is selected from polyether, polyvinyl alcohol and polyvinyl pyrrolidone, and the hydrophobic side chain is polyethylene. , Polyolefin, polystyrene, polyester, polyurethane, polyamide, polyvinyl acetate, and an acrylic resin. The method for producing a conductive polymer suspension solution according to claim 10 , wherein the monomer that provides the conductive polymer is at least one selected from pyrrole, thiophene, and derivatives thereof. The conductive polymer suspension according to claim 10 or 11 , wherein the dopant is at least one selected from benzenesulfonic acid, naphthalenesulfonic acid, camphorsulfonic acid and derivatives thereof, and salts thereof. A method for producing a turbid solution. The method for producing a conductive polymer suspension solution according to any one of claims 10 to 12 , wherein the first step is performed in the presence of a substance having a surfactant activity. In the second step, the conductive polymer, conductive according to any one of claims 10 to 13, wherein the washing with the monomer and / or the possible dissolution of the oxidizing agent solvent A method for producing a polymer suspension. The method for producing a conductive polymer suspension solution according to any one of claims 10 to 14 , wherein polystyrene sulfonic acid is used as the polyanion in the third step. The method for producing a conductive polymer suspension solution according to claim 15 , wherein the polystyrenesulfonic acid has a weight average molecular weight of 2,000 to 500,000. The conductive polymer suspension solution according to any one of claims 10 to 16 , wherein in the fourth step, the conductive polymer suspension is pulverized so that the particle size of the conductive polymer is 100 nm or less. Production method. With respect to the conductive polymer 100 parts by weight, either the polyacid 10 to 200 parts by weight, of claims 10 to 17 dispersing agent having the structure of the branch type is characterized in that 1 to 120 parts by weight A method for producing a conductive polymer suspension solution according to claim 1. The method for producing a conductive polymer suspension solution according to any one of claims 10 to 18 , wherein at least one water-soluble binder is mixed during or after the fourth step. The method for producing a conductive polymer suspension solution according to claim 19 , wherein the water-soluble binder is at least one of polyester and polyamide. 21. The method for producing a conductive polymer suspension according to claim 19 or 20 , wherein 10 to 400 parts by weight of at least one water-soluble binder is mixed with 100 parts by weight of the conductive polymer. . The method for producing a conductive polymer suspension solution according to any one of claims 10 to 21 , wherein erythritol and / or pentaerythritol are mixed during or after the fourth step. A conductive polymer suspension solution obtained by the method according to any one of claims 10 to 22 . 24. A conductive polymer material obtained by drying the conductive polymer suspension solution according to any one of claims 1 to 9 and 23 and removing the solvent. An electrolytic capacitor comprising an electrolyte layer containing the conductive polymer material according to claim 24 . 26. The method according to claim 25 , comprising an anode conductor made of a valve metal and a dielectric layer formed on a surface of the anode conductor, wherein the electrolyte layer is formed on the dielectric layer. The electrolytic capacitor as described. Forming a dielectric layer on the surface of the anode conductor made of a valve metal;
Applying or impregnating the conductive polymer suspension solution according to any one of claims 1 to 9 and claim 23 on the dielectric layer to form an electrolyte layer. A method for manufacturing an electrolytic capacitor. Forming a dielectric layer on the surface of the anode conductor made of a valve metal;
Forming a first conductive polymer compound layer on the dielectric layer by chemical oxidative polymerization or electrolytic polymerization of a monomer that gives the first conductive polymer compound;
A conductive polymer suspension solution according to any one of claims 1 to 9 and claim 23 is applied or impregnated on the first conductive polymer compound layer, and the second conductive polymer is coated. And a step of forming a compound layer. The method for producing an electrolytic capacitor according to claim 28 , wherein the first conductive polymer compound is at least one polymer selected from pyrrole, thiophene, aniline, and derivatives thereof. The valve metal is aluminum, method of manufacturing an electrolytic capacitor according to any one of claims 27 to 29, characterized in that at least one selected from tantalum and niobium.

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